자가면역성 장기 코로나에서의 면역흡착 (TURNLongCOVID)

Participants in the placebo group will receive six sessions of sham treament, each lasting 2.5 hours over two weeks. The procedure will be performed without an adsorption column, allowing the blood to circulate through the extracorporeal circuit and be returned to the patient without removal of immunoglobulins or other plasma components.

The immunoadsorption column will be removed from the device, so that the patient's blood passes through the system and is returned to the body without undergoing adsorption or removal of antibodies.

Participants in the intervention group will receive six sessions of immunoadsorption, each lasting 2.5 hours over two weeks. Immunoadsorption will be performed using tryptophan columns, which bind the Fc region of IgG via hydrophobic and aromatic interactions.

Immunoadsorption will be performed using tryptophan columns, which bind the Fc region of IgG via hydrophobic and aromatic interactions.

Score range 10-50 (10 items, Likert scale 1-5). Higher scores indicate more severe fatigue (worse). The difference in scores from baseline will be measured (MCID of 4 points) as the primary outcome.

Eight domains scored from 0-100. Domain scores are commonly summarized into the Physical Component Summary (PCS) and Mental Component Summary (MCS) (norm-based, mean 50, SD 10). Higher scores indicate better health-related quality of life and functioning.

Raw scores are converted to T-scores (20-80), with a population mean of 50 (SD 10). Higher scores indicate better cognitive functioning. Change in score will be measured (MCID 3-5).

0-100 weighted total score across six domains: orthostatic intolerance, vasomotor, secretomotor, gastrointestinal, bladder, and pupillomotor symptoms. Higher scores indicate greater autonomic symptom burden.

All AEs and SAEs will be recorded, graded according to CTCAE v5.0, and assessed for relatedness to the study treatment. Specific attention will be given to complications of extracorporeal procedures (e.g., hypotension, bleeding, allergic reactions, infection, and vascular access issues)

Handgrip strength will be assessed using a calibrated handheld dynamometer at four standardized measurement points in accordance with the American Society of Hand Therapists (ASHT) guidelines. Grip strength will be recorded in kilograms (kg). Higher grip strength reflects better muscle function.

The NASA Lean Test is a standardized active standing test used to assess orthostatic intolerance. Participants rest in a supine position followed by an active standing phase while leaning against a wall to minimize skeletal muscle pumping. Heart rate and blood pressure are measured at predefined intervals during standing. Abnormal heart rate and/or blood pressure responses during the test indicate orthostatic intolerance.

Immunoglobulin G titers will be measured in blood samples using standardized laboratory assays and reported as concentrations (g/L).

For this assay, IgG will be isolated from patient serum samples obtained during screening and analyzed using a Luminex-based multiplex immunoassay targeting a panel of 15 validated autoantigens. A weighted scoring system is applied to the resulting autoantibody signals.